Oral or buccal drug delivery is a highly favoured route of drug administration in the pharmaceutical industry due to factors such as patient preference for the oral route over other routes of drug administration. Patient compliance with oral drug delivery is a result of low cost, the ease and avoidance of pain upon administration, as well as a decrease in the risk of infections that are associated with parenteral dosage forms. Furthermore, the relatively large fluid volume available, the increased mucosal area available for absorption and the profuse blood supply to the gastric mucosa aids the absorption of many drugs. The success of orally delivered drugs is principally dependant on the transit of the drug delivery system (DDS) through the GIT. In addition to this, many drugs are absorbed at specific sites within the gastro intestinal tract (GIT) i.e. narrow absorption window (NAW) drugs. As conventional tablets and capsules are transported through the GIT, they release the drug into non-specific regions within the GIT. If the drug is not released in sufficient quantities at the site of absorption, the drug will not reach effective plasma drug concentrations to achieve the desired therapeutic effect. Thus many drugs are poorly absorbed, such as NAW drugs or drugs which are sensitive to gastric juices and enzymes, i.e. proteins and peptides. In many instances, oral prolonged release formulations provide lower bioavailability as compared to immediate release formulations, as release from the prolonged release formulations is not completed during transit of the delivery system through the GIT [5]. In addition, conventional drug delivery systems deliver drug in a peak-to-trough pattern, with the peaks usually being above the required dose, and therefore prolonged release systems would be preferred to relatively fast release systems [6].